There has been known an image pick-up device (e.g., a camera or a video camera) provided with a function for enabling the device to automatically adjust a focus and brightness for a certain object in an object space to be picked up, so that the image of the certain object is picked up more clearly.
For example, Patent Literatures 1 to 4 each disclose an image pick-up device that recognizes, as a certain object, a person in an object space to be picked up, and automatically adjusts a focus and brightness for the person. Specifically, each image pick-up device disclosed in Patent Literatures 1 to 4 recognizes the person (or the face of the person) by (i) extracting e.g., a luminance distribution and a color signal level distribution from the image of the object space to be picked up and (ii) detecting, in accordance with the distributions, a skin-color region and a feature such as an eye, a nose, and/or a mouth in the image. Further, in order to clearly pick up an image of the recognized person, the image pick-up device corrects the values of e.g., a focus, a white color temperature (white balance), and the amount of light exposure (the amount of light) measured during the image pick-up so that these values attain appropriate values.
However, in each image pick-up device in Patent Literatures 1 to 4, such a configuration is not disclosed that adjusts a focus and brightness for a desired person in a case where a plurality of persons exist in an object space to be picked up. Therefore, Patent Literatures 1 to 4 have a problem that, in the case where a plurality of persons exist in an object space to be picked up, the image pick-up device, which automatically adjusts a focus and brightness, cannot adjust the focus and brightness for the desired person.
In order to deal with this problem, for example, Patent Literatures 5 and 6 each disclose an image pick-up device that requires a user to optionally select an object to be subjected to adjustment of a focus and brightness. Specifically, Patent Literature 5 discloses an image pick-up device that registers a feature of an object optionally selected by a user, and identifies the object in accordance with the feature registered, so as to adjust a focus and brightness for the object. Patent Literature 6 discloses an image pick-up device that registers features of objects in advance, and identifies, in accordance with the features registered, an object optionally selected by a user from among the objects whose features have been registered, so as to adjust a focus and brightness for the object.
Patent Literature 7 discloses an information terminal device and an authentication system, each including a registration program for enabling learning and registration of the image data of a user.